Cisco Sg3008 Manual

							Multicast
Defining Unregistered Multicast Settings
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IGMP or MLD messages are not forwarded to ports defined as For ward All.
NOTEThe configuration affects only the ports that are members of the selected VLAN.
To define Forward All Multicast:
STEP 1Click Multicast > Forward All.
STEP  2Define the following:
•VLAN ID equals to—The VLAN ID the ports/LAGs are to be displayed.
•Interface Type equals to—Define whether to display ports or LAGs.
STEP  3Click Go. The status of all ports/LAGs are displayed.
STEP  4Select the port/LAG that is to be defined as Forward All by using the following 
methods: 
•Static—The port receives all Multicast streams. 
•Forbidden—Ports cannot receive any Multicast streams, even if IGMP/MLD 
snooping designated the port to join a Multicast group.
•None—The port is not currently a Forward All port.
STEP  5Click Apply. The Running Configuration file is updated.
Defining Unregistered Multicast Settings
Multicast frames are generally forwarded to all ports in the VLAN. If IGMP/MLD 
Snooping is enabled, the device learns about the existence of Multicast groups, 
and monitors which ports have joined which Multicast group. Multicast groups can 
also be statically configured. Multicast groups that were either dynamically 
learned or statically configured, are considered registered. 
The device forwards Multicast frames (from a registered Multicast group) only to 
ports that are registered to that Multicast group.
The Unregistered Multicast page enables handling Multicast frames that belong to 
groups that are not known to the device (unregistered Multicast groups). 
Unregistered Multicast frames are usually forwarded to all ports on the VLAN.  
						

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Defining Unregistered Multicast Settings
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You can select a port to receive or filter unregistered Multicast streams. The 
configuration is valid for any VLAN of which it is a member (or will be a member).
This feature ensures that the customer receives only the Multicast groups 
requested and not others that may be transmitted in the network. 
To define unregistered Multicast settings:
STEP 1Click Multicast > Unregistered Multicast.
STEP  2Define the following:
•Interface Type equals to—The view as all ports or all LAGs. 
•Port/LAG—Displays the port or LAG ID.
•Unregistered Multicast—Displays the forwarding status of the selected 
interface. The possible values are:
-For warding—Enables forwarding of unregistered Multicast frames to the 
selected interface. 
-Filtering—Enables filtering (rejecting) of unregistered Multicast frames to 
the selected interface.
STEP  3Click Apply. The settings are saved, and the Running Configuration file is updated. 
						

							Multicast
Defining Unregistered Multicast Settings
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IP Configuration
IP interface addresses can be configured manually by the user, or automatically 
configured by a DHCP server. This section provides information for defining the 
device IP addresses, either manually or by making the device a DHCP client.
This section covers the following topics:
•Overview
•IPv4 Management and Interfaces
•DHCP Server
•IPv6 Management and Interfaces
•Domain Name
Overview
Some features are only available in Layer 2 or Layer 3 system mode, as described 
below: 
•In Layer 2 system mode, the device operates as a Layer 2 VLAN-aware 
device, and has no routing capabilities.
•In Layer 3 system mode, the device has IP routing capabilities as well as 
Layer 2 system mode capabilities. In this system mode, a Layer 3 port still 
retains much of the Layer 2 functionality, such as Spanning Tree Protocol 
and VLAN membership.
In Layer 3 system mode, the device does not support MAC-based VLAN, 
Dynamic VLAN Assignment, VLAN Rate Limit, SYN Rate DoS Protection, 
and Advanced QoS Policers.
Configuring the device to work in either mode is performed in the Administration > 
System Settings page.  
						

							IP Configuration
Overview
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NOTESwitching from one system mode (layer) to another (on Sx500 devices) requires a 
mandatory reboot, and the startup configuration of the device is then deleted. 
Layer 2 IP Addressing
In Layer 2 system mode, the device has up to one IPv4 address and up to two IPv6 
interfaces (either “native” interface or Tunnel) in the management VLAN. This IP 
address and the default gateway can be configured manually, or by DHCP. The 
static IP address and default gateway for Layer 2 system mode are configured on 
the IPv4 Interface and IPv6 Interfaces pages. In Layer 2 system mode, the device 
uses the default gateway, if configured, to communicate with devices that are not 
in the same IP subnet with the device. By default, VLAN 1 is the management 
VLAN, but this can be modified. When operating in Layer 2 system mode, the 
device can only be reached at the configured IP address through its management 
VLAN.
The factory default setting of the IPv4 address configuration is DHCPv4. This 
means that the device acts as a DHCPv4 client, and sends out a DHCPv4 request 
during boot up. 
If the device receives a DHCPv4 response from the DHCPv4 server with an IPv4 
address, it sends Address Resolution Protocol (ARP) packets to confirm that the IP 
address is unique. If the ARP response shows that the IPv4 address is in use, the 
device sends a DHCPDECLINE message to the offering DHCP server, and sends 
another DHCPDISCOVER packet that restarts the process. 
If the device does not receive a DHCPv4 response in 60 seconds, it continues to 
send DHCPDISCOVER queries, and adopts the default IPv4 address: 
192.168.1.254/24. 
IP address collisions occur when the same IP address is used in the same IP 
subnet by more than one device. Address collisions require administrative actions 
on the DHCP server and/or the devices that collide with the device.
When a VLAN is configured to use dynamic IPv4 addresses, the device issues 
DHCPv4 requests until it is assigned an IPv4 address from a DHCPv4 server. In 
Layer 2 system mode, only the management VLAN can be configured with a static 
or dynamic IP address. In Layer 3 system mode, all the interface types (ports, 
LAGs, and/or VLANs) on the device can be configured with a static or dynamic IP 
address. 
The IP address assignment rules for the device are as follows: 
•When in Layer 2 system mode, unless the device is configured with a static 
IP address, it issues DHCPv4 requests until a response is received from the 
DHCP server. 
						

							IP Configuration
Overview
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•If the IP address on the device is changed, the device issues gratuitous ARP 
packets to the corresponding VLAN to check IP address collisions. This rule 
also applies when the device reverts to the default IP address.
•The system status LED changes to solid green when a new unique IP 
address is received from the DHCP server. If a static IP address has been 
set, the system status LED also changes to solid green. The LED flashes 
when the device is acquiring an IP address and is currently using the factory 
default IP address 192.168.1.254.
•The same rules apply when a client must renew the lease, prior to its 
expiration date through a DHCPREQUEST message.
•With factory default settings, when no statically-defined or DHCP-acquired 
IP address is available, the default IP address is used. When the other IP 
addresses become available, the addresses are automatically used. The 
default IP address is always on the management VLAN.
Layer 3 IP Addressing
In Layer 3 system mode, the device can have multiple IP addresses. Each IP 
address can be assigned to specified ports, LAGs, or VLANs. These IP addresses 
are configured in the IPv4 Interface and IPv6 Interfaces pages in Layer 3 system 
mode. This provides more network flexibility than the Layer 2 system mode, in 
which only a single IP address can be configured. Operating in Layer 3 system 
mode, the device can be reached at all its IP addresses from the corresponding 
interfaces. 
A predefined, default route is not provided in Layer 3 system mode. To remotely 
manage the device, a default route must be defined. All DHCP-assigned default 
gateways are stored as default routes. In addition, you can manually define default 
routes. This is defined in the IPv4 Static Routes and IPv6 Routes pages.
All the IP addresses configured or assigned to the device are referred to as 
Management IP addresses in this guide.
If the pages for Layer 2 and Layer 3 are different, both versions are displayed. 
						

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Overview
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Loopback Interface
Overview
The loopback interface is a virtual interface whose operational state is always up. 
If the IP address that is configured on this virtual interface is used as the local 
address when communicating with remote IP applications, the communication will 
not be aborted even if the actual route to the remote application was changed.
The operational state of a loopback interface is always up. You define an IP 
address  (either IPv4 or IPv6) on it and use this IP address as the local IP address 
for IP communication with remote IP applications.
A loopback interface does not support bridging; it cannot be a member of any 
VLAN, and no layer 2 protocol can be enabled on it.
The IPv6 link-local interface identifier is 1. 
When the switch is in Layer 2 system mode, the following rules are supported:
•Only one loopback interface is supported. 
•Two IPv4 interfaces can be configured: one on a VLAN or Ethernet port and 
one on the loopback interface.
•If the IPv4 address was configured on the default VLAN and the default 
VLAN is changed, the switch moves the IPv4 address to the new default 
VLAN.
Configuring a Loopback Interface
To configure an IPv4 loopback interface, do the following:
•In Layer 2, enable Loopback Interface and configure its address in 
Administration > Management Interface > IPv4 Interface page. 
•In Layer 3, add a loopback interface in IP Configuration > IPv4 Management 
and Interfaces > IPv4 Interface.
To configure an IPv6 loopback interface, do the following:
•In Layer 2, add a loopback interface in the Administration > Management 
Interface > IPv6 Interfaces page. Configure the IPv6 address of that 
interface in the Administration > Management Interface > IPv6 Addresses 
page. This page is not available in SG500X, ESW2-550X and SG500XG 
devices. 
						

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IPv4 Management and Interfaces
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•In Layer 3, add a loopback interface in IP Configuration > IPv6 Management 
and Interfaces > IPv6 Interface. Configure the IPv6 address of that interface 
in the IP Configuration > IPv6 Management and Interfaces > IPv6 Addresses 
page. 
IPv4 Management and Interfaces
IPv4 Interface
IPv4 interfaces can be defined on the device when it is in Layer 2 or Layer 3 
system mode.
Defining an IPv4 Interface in Layer 2 System Mode 
To manage the device by using the web-based configuration utility, the IPv4 
device management IP address must be defined and known. The device IP 
address can be manually configured or automatically received from a DHCP 
server.
To configure the IPv4 device IP address:
STEP 1Click Administration > Management Interface > IPv4 Interface.
STEP  2Enter values for the following fields:
•Management VLAN—Select the Management VLAN used to access the 
device through telnet or the Web GUI. VLAN1 is the default Management 
VLAN.
•IP Address Type—Select one of the following options:
-
Dynamic—Discover the IP address using DHCP from the management 
VLAN.
-
Static—Manually define a static IP address. 
NOTEDHCP Option 12 (Host Name option) is supported when the device is 
a DHCP client. If DHCP Option 12 is received from a DHCP server, it is saved 
as the server ’s host name. DHCP option 12 will not be requested by the 
device. The DHCP server must be configured to send option 12, regardless 
of what is requested in order to make use of this feature.  
						

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To configure a static IP address, configure the following fields.
•IP Address—Enter the IP address, and configure one of the following Mask 
fields:
-Network Mask—Select and enter the IP address mask.
-Prefix Length—Select and enter the length of the IPv4 address prefix.
•Loopback Interface—Select to enable the configuration of a loopback 
interface (see Loopback Interface).
•Loopback IP Address—Enter the IPv4 address of the loopback interface.
Enter one of the following fields for the loopback interface:
-Lo opba ck Ma sk—Enter the mask of the IPv4 address of the loopback 
interface.
-Prefix Length—Enter the prefix length of the IPv4 address of the 
loopback interface.
•Administrative Default Gateway—Select User Defined and enter the 
default gateway IP address, or select None to remove the selected default 
gateway IP address from the interface. 
•Operational Default Gateway—Displays the current default gateway 
status. 
NOTEIf the device is not configured with a default gateway, it cannot 
communicate with other devices that are not in the same IP subnet.
If a dynamic IP address is retrieved from the DHCP server, select those of the 
following fields that are enabled:
•Renew IP Address Now—The device dynamic IP address can be renewed 
any time after it is assigned by a DHCP server. Note that depending on your 
DHCP server configuration, the device might receive a new IP address after 
the renewal that requires setting the web-based configuration utility to the 
new IP address. 
•Auto Configuration via DHCP—Displays status of Auto Configuration 
feature. You can configure this from 
Administration > File Management > 
DHCP Auto Configuration.
STEP  3Click Apply. The IPv4 interface settings are written to the Running Configuration 
file. 
						

							IP Configuration
IPv4 Management and Interfaces
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Defining IPv4 Interface in Layer 3 System Mode 
The IPv4 Interface page is used when the device is in Layer 3 system mode. This 
mode enables configuring multiple IP addresses for device management, and 
provides routing services. 
The IP address can be configured on a port, a LAG, VLAN or loopback interface.
Operating in Layer 3 mode, the device routes traffic between the directly-
attached IP subnets configured on the device. The device continues to bridge 
traffic between devices in the same VLAN. Additional IPv4 routes for routing to 
non-directly attached subnets can be configured in the IPv4 Static Routes page.
NOTEThe device software consumes one VLAN ID (VID) for every IP 
address configured on a port or LAG. The device takes the first VID that is 
not used starting from 4094. 
To configure the IPv4 addresses:
STEP 1Click IP Configuration > IPv4 Management and Interfaces > IPv4 Interface.
This page displays the following fields in the IPv4 Interface Table:
•Interface—Interface for which the IP address is defined.
•IP Address Type—IP address defined as static or DHCP.
-Dynamic IP Address—Received from DHCP server.
-Static—Entered manually.
•IP Address—Configured IP address for the interface.
•Mask—Configured IP address mask.
•Status—Results of the IP address duplication check.
-Te n t a t i v e—There is no final result for the IP address duplication check. 
-Valid—The IP address collision check was completed, and no IP address 
collision was detected. 
-Valid-Duplicated—The IP address duplication check was completed, 
and a duplicate IP address was detected. 
-Duplicated—A duplicated IP address was detected for the default IP 
address.